枸杞岛紫贻贝生长状况及其与环境因子关系

Growth conditions of Mytilus edulis Linnaeus and its relationship with environmental factors in Gouqi Island

针对嵊泗马鞍列岛国家海洋特别保护区内枸杞岛海域开放式浮筏式养殖紫贻贝(Mytilus edulis Linnaeus)生长存在差异[组织干重(0.200±0.017)g]的现象,利用SPSS 16.0统计软件中方差分析和相关性分析对紫贻贝生长及其与环境因子之间关系进行研究。结果表明:水体中叶绿素含量[(15.73±5.724)mg/L]、颗粒有机物(POM)浓度[(5.43±1.092)mg/L]和颗粒有机物与悬浮颗粒物(SPM)比值(0.200±0.057)对紫贻贝生长影响显著(P<0.05)。其中,POM与SPM的比值对紫贻贝生长的影响最大。从水动力角度探究影响POM和SPM分布的原因,使用声学多普勒流速剖面仪(ADCP)对该海域流态进行监测发现,紫贻贝浮筏式吊养设施对该养殖海域水流交换产生重要影响,潮流从表层(L1MAX31.88 cm/s)至底层(L1MAX37.68 cm/s)逐渐增大,且涨落潮迎流面的流速(L1MAX31.88 cm/s,L3MAX35.53 cm/s)大于养殖区内部流速(L2MAX20.21cm/s)。养殖区域内水流的交换影响浮游生物及颗粒有机物等饵料的分布,饵料分布对紫贻贝生长产生影响。养殖区域外围的贻贝生长速度(0.017 g/M)显著高于中间区域的贻贝生长速度(0.011 g/M)。因此,在大规模的贻贝养殖区内,合理规划养殖区块,沿着潮流方向预留相应的通道以改善贻贝养殖区域内部的水交换程度具有重要意义。

There are differences in the growth of Mytilus edulis Linnaeus farmed with floating raft,around the Gouqi Island waters in the National Marine Special Reserve of Shengsi Ma’an Archipelago.Growth conditions of Mytilus edulis Linnaeus and its relationship with environmental factors are studied using analysis of variance and correlation analysis with the SPSS 16.0 statistical software.Results show that the chlorophyll content,the concentration of particulate organic matter（POM）,and the ratio of POM and suspended particulate matter（SPM）,have significant effects on the growth of Mytilus edulis Linnaeus.Among them,the third has the biggest significance.Exploring the impact of POM and SPM distribution from the hydrodynamic point of view,the water flow was monitored by Acoustic Doppler Current Profilers（ADCP） and result shows that suspending facilities in the water like floating rafts of Mytilus edulis Linnaeus would have important effects on water exchange of this area.Tidal velocity gradually increases from the surface to the bottom and velocities of flows facing the rising tide and falling tide are greater than that within the culturing zone.Water exchange within the culturing zone would have influence on the distribution of baits like phytoplankton and POM,and consequently,the distribution of baits would affect the growth of Mytilus edulis Linnaeus.The growth rate of Mytilus edulis Linnaeus outside of the culturing zone is obviously higher than that within the zone.Therefore,appropriately planning the culturing blocks in large scale of mussel culturing zone is desirable by leaving some areas blank as passageways along the tidal flow to improve water exchange within the mussel culturing zone,which has great importance.